package com.chb.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.stereotype.Component;

import java.lang.annotation.Annotation;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLB implements LoadBalancer {

    private AtomicInteger atomicInteger = new AtomicInteger(0);


    public  final  int getAndIncrement(){
        int current;
        int next;
        do{
            current = this.atomicInteger.get();
            next = current >= Integer.MAX_VALUE ? 0 :current +1;

        }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("第几次访问，next : "+next);

        return next;

    }
    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}
